Significantly higher median levels of serum cytokines, IL-1β and IL-18, were observed in AOSD-active patients (median 3.86 pg/mL, IQR 1.83-5.20 pg/mL; 5757.5 pg/mL, 824.3-27657.0 pg/mL; respectively) compared with HCs (1.37 pg/mL, 0.87-2.15 pg/mL; 167.1 pg/mL, 79.5-297.2 pg/mL; respectively, both p < 0.001). Here, IL1B is linked to adult-onset Still disease.